Efficacy of mindfulness to regulate induced emotions in the laboratory: A systematic review and meta-analysis of self-report and biobehavioral measures.

A substantial part of the research on the efficacy of mindfulness-based interventions on mood regulation is conducted in the laboratory. Nevertheless, a systematic review of the results is lacking. This meta-analysis aimed to investigate the effects of mindfulness as an emotion regulation (ER) strategy when using mood induction procedures. A systematic search of databases was conducted and a total of 43 studies were included in the meta-analysis. We found a small significant overall effect size of mindfulness [g= -0.15 (95% CI [-0.30, -0.01], p = 0.04)], which became non-significant after removing outliers (g=-0.15, p = 0.06). We also found high levels of heterogeneity which was not explained by the moderating variables analyzed. Thus, there is limited meta-analytic evidence of the efficacy of mindfulness strategies in down-regulating or preventing heightened or chronic effects of induced mood states in well-controlled laboratory settings. We propose that this could be partially due to some limitations in laboratory methodologies and suggest some guidelines to overcome them in future primary research.